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Copernicus/Transcript
Transcript Text reads: The Mysteries of Life with Tim and Moby. A boy, Tim, and a robot, Moby, are in their backyard under a clear, night sky. Moby is lying on his back in the grass, listening to Strauss' "Blue Danube" - performed by Vienna State Opera Orchestra and conducted by Peter Falk - on his headphones. His eyes are closed. Tim is gazing at the heavens through his telescope. TIM: Hey, check it out. Europa. Moby does not respond. Tim reaches to nudge him. TIM: Hey. Moby hands Tim a sheet of paper. Tim reads from the typed letter. TIM: Dear Tim and Moby, If the earth orbits the sun, how come we can't feel it moving? Thanks, Hanz. Great question, Hanz. Even the brilliant minds of Ancient Greece had a tough time with this one. They saw the sun rise and set every day. At night, the stars moved across the sky. And, like us, they couldn't feel the planet moving. An animation shows a philosopher in Ancient Greece. He is sitting beneath a tree, watching the sun, moon, and stars pass overhead. TIM: All of these observations supported a geocentric model. MOBY: Beep. TIM: That's the idea that Earth stands motionless in the center of the universe, and that everything else revolves around us. The Greek philosopher Aristotle based his whole system of astronomy on this idea. An animation shows Aristotle drawing a geocentric model of the universe in the dirt with a stick. MOBY: Beep. TIM: He saw the universe as a set of transparent shells. Each object in the sky was attached to one of these celestial spheres. An animation shows the celestial spheres that Tim describes. Smaller spheres sit inside larger spheres, and each has a heavenly body attached to it. TIM: Beyond them lay the sphere of the Prime Mover. A large hand appears, holding the arrangement of concentric spheres in place. TIM: It was the engine of the system, triggering the motion of the sun, moon, and planets. MOBY: Beep. TIM: Laugh all you want, but Aristotle's system had its uses. It could predict the positions of planets and stars in the sky, roughly. An animation shows an ancient astronomer using a simple sextant and a geocentric model of the solar system to locate heavenly bodies in the night sky. TIM: So, people stuck with it, despite a few inaccuracies. MOBY: Beep. TIM: Aristotle's model didn't explain why some planets looked brighter at different times of the year. Or why some planets seemed to reverse direction. An animation shows a planet in the night sky, moving as Tim describes. TIM: A Roman astronomer named Ptolemy figured out the model was just incomplete. An animation shows Ptolemy coming up with an idea. Instead of a lightbulb appearing over his head, there's a lamp with a flame. MOBY: Beep. TIM: In his view, planets weren't directly attached to celestial spheres. They rotated around them in perfect circles he called epicycles. Animations illustrate the simple geocentric model and Ptolemy's notion of epicycles. TIM: As they moved along their epicycle, planets would appear brighter when closer to Earth. This also explained why planets might seem to hover in position or move backwards. Side by side animations show a planet moving around loops or epicycles in a celestial sphere, and a planet shifting back and forth in space. MOBY: Beep. TIM: Ptolemy added more and more epicycles to fill in all of Aristotle's blanks. The Ptolemaic model was complicated, but also incredibly accurate. An animation shows Ptolemy at a blackboard, drawing his complicated model. TIM: It predicted the exact position of every observable object in the night sky, so it continued to be used for more than 1,000 years. MOBY: Beep. TIM: Many astronomers after Ptolemy were clerics, scholars in the Catholic Church. An animation shows a medieval Catholic clergyman standing at a blackboard that displays Ptolemy's model. He pulls down a screen that displays an image of Aristotle's geocentric spheres with the Prime Mover's hand at the top. TIM: The Church approved of the geocentric model because it fit so well with Christian thought. The Prime Mover was obviously God. And humans were his central focus, positioned smack in the middle of all the action. The Catholic clergyman is instructing a class, using the image on the pull-down screen. TIM: But a Polish cleric named Nicolaus Copernicus started to notice some problems. Copernicus is in the clergyman's class. He raises his hand and looks inquisitive. MOBY: Beep. TIM: He didn't totally reject the geocentric model. Copernicus just thought it needed some adjustments. An animation shows Copernicus in a huge library, studying books on astronomy. TIM: To his surprise, he found many alternatives to geocentrism, dating back to the Greeks. Reading these ideas helped him develop an entirely new vision. An image shows four of the astronomy books Copernicus is reading. MOBY: Beep. TIM: What if the rising and setting of the sun was not related to its motion, but the spinning of our own planet? An animation shows the sun going orbiting Earth. The sun stops its motion, and the sound of screeching brakes is heard. TIM: And what if all the planets, including Earth, revolved around the sun. Any time Earth passed another planet, it would look like that planet was reversing direction. An animation shows Earth and the other planets rotating as they revolve around the sun. TIM: For the next 15 years, Copernicus worked out his heliocentric model. An animation shows Copernicus at a blackboard, plotting out his sun-centered conception of the solar system. TIM: He added the suggestion that the earth was tilted. That would explain the yearly cycle of the seasons. The animation shows Copernicus drawing a picture of a Sun and a tilted Earth. MOBY: Beep. TIM: Copernicus was a very religious guy. He didn't want to undermine the Church's position. So, he waited until the end of his life to share his theories. An animation shows a cleric handing an elderly Copernicus a copy of Copernicus' book, called ''On the Revolutions of the Heavenly Spheres. '''TIM:' As expected, they met with a lot of controversy. MOBY: Beep. TIM: On a gut level, it was difficult to accept. If the earth was spinning, how come a rock tossed into the air didn't land somewhere else? And if it was moving around the sun, why couldn't we feel its speed? An animation shows a woman standing on a slowly rotating globe. She tosses a rock straight upward, she moves beneath it, and it falls back to Earth behind her. Air blows her dress from the rotation of the globe. TIM: Clerics pointed out that the new system couldn't make accurate predictions without lots of complex math. But more importantly, it contradicted the Church and the wisdom of the Greeks. Humans were supposed to be the main characters in the unfolding story of our universe. An animation shows a man standing triumphantly atop a globe, with both the Sun and the Moon revolving around him. TIM: If Copernicus was right, we were just spectators. This radical shift is now known as the Copernican Revolution. Side by side images compare Ptolemy's model of the universe to that of Copernicus. MOBY: Beep. TIM: There weren't any armies or battles. It was a revolution in thought. The wisdom of the past faced off against open-minded explorations of the world. An animation shows Ptolemy and Copernicus playing cards in front of their models of the universe. The cards are labeled "Science: The Universe." TIM: Direct observation competed with faith in trying to explain the unknown. MOBY: Beep. TIM: Over time, people had to accept what they could see with their own eyes. The Danish astronomer, Tycho Brahe, discovered a comet traveling on a path that would have shattered most of the celestial spheres. An animation shows that the cards Ptolemy and Copernicus are holding contain information about important astronomers. Copernicus examines a card about Tycho Brahe and plays it on the table. Behind him a comet shatters the spheres on Ptolemy's model of the universe. TIM: One of his students, Johannes Kepler, showed that planets move in ellipses, not circles. That solved the math problems that had plagued Copernicus' model. The animation shows Copernicus placing a Johannes Kepler card atop his Tycho Brahe card. The circles on Copernicus' model transform into ellipses. TIM: Finally, Galileo observed moons orbiting Jupiter. Since everything was supposed to orbit the earth, that was the end of geocentrism. Copernicus plays a Galileo card, along with several others. Then he jumps up from his chair and does a victory dance. Ptolemy places his face in his hands as his universe model shatters. MOBY: Beep. TIM: As for the Prime Mover, Isaac Newton showed that the force of gravity was sufficient to move the stars and planets. An animation shows Isaac Newton sitting beneath a tree, being hit on the head by a falling apple, and thinking about what just happened to him. TIM: He also explained why it seems like the earth is completely still. When motion is constant and steady, you don't feel it. Just like in an airplane, or a car on the highway. Animations show the earth revolving around the Sun, an airplane flying through the air, and a girl inside an airplane tossing an apple straight up and down. TIM: Now, if the earth changed speed or direction, we'd definitely feel that. As Tim looks through his telescope, Moby smiles and starts to press buttons on a control panel in his arm. Still gazing at the sky, Tim grabs Moby's arm to stop him. TIM: Do not stop the planet, thank you very much.Category:BrainPOP Transcripts